The third edition of the WMO–IRENA Year in Review examines how climate variability and long-term climate change affect renewable energy resources and electricity demand at global and regional levels. Using climate-driven indicators for wind, solar and hydropower, together with temperature-based energy demand metrics, the report assesses regional renewable energy system performance during 2024, the warmest year on record, compared with the 1991–2020 average. The analysis highlights strong regional contrasts driven by climate extremes, residual El Niño conditions and record ocean heat, while global climate-driven energy demand increased by around 4%. As global renewable energy capacity exceeds 4,400 GW, the report underscores the growing interaction between climate and energy systems and demonstrates how seasonal climate forecasts, climate intelligence and early warning systems can support energy planning, investment and resilience in line with the Paris Agreement and COP28 energy targets.